/* Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.activiti.engine.impl.cmd;

import java.io.Serializable;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.impl.context.Context;
import org.activiti.engine.impl.identity.Authentication;
import org.activiti.engine.impl.interceptor.Command;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.impl.persistence.entity.CommentEntity;
import org.activiti.engine.impl.persistence.entity.CommentManager;
import org.activiti.engine.impl.persistence.entity.TaskEntity;
import org.activiti.engine.impl.util.ClockUtil;
import org.activiti.engine.task.Event;
import org.activiti.engine.task.IdentityLinkType;

/**
 * @author Joram Barrez
 */
public class AddIdentityLinkCmd implements Command<Void>, Serializable {

	private static final long serialVersionUID = 1L;

	protected String taskId;

	protected String userId;

	protected String groupId;

	protected String type;

	public AddIdentityLinkCmd(String taskId, String userId, String groupId,
			String type) {
		validateParams(userId, groupId, type, taskId);
		this.taskId = taskId;
		this.userId = userId;
		this.groupId = groupId;
		this.type = type;
	}

	protected void validateParams(String userId, String groupId, String type,
			String taskId) {
		if (taskId == null) {
			throw new ActivitiException("taskId is null");
		}

		if (type == null) {
			throw new ActivitiException(
					"type is required when adding a new task identity link");
		}

		// Special treatment for assignee, group cannot be used an userId may be
		// null
		if (IdentityLinkType.ASSIGNEE.equals(type)) {
			if (groupId != null) {
				throw new ActivitiException(
						"Incompatible usage: cannot use ASSIGNEE"
								+ " together with a groupId");
			}
		} else {
			if (userId == null && groupId == null) {
				throw new ActivitiException(
						"userId and groupId cannot both be null");
			}
		}
	}

	public Void execute(CommandContext commandContext) {
		TaskEntity task = Context.getCommandContext().getTaskManager()
				.findTaskById(taskId);

		if (task == null) {
			throw new ActivitiException("Cannot find task with id " + taskId);
		}

		if (IdentityLinkType.ASSIGNEE.equals(type)) {
			task.setAssignee(userId);
		} else if (IdentityLinkType.OWNER.equals(type)) {
			task.setOwner(userId);
		} else {
			task.addIdentityLink(userId, groupId, type);
		}

		// CommentManager commentManager = commandContext.getCommentManager();
		// if (commentManager.isHistoryEnabled()) {
		// String authenticatedUserId = Authentication.getAuthenticatedUserId();
		// CommentEntity comment = new CommentEntity();
		// comment.setUserId(authenticatedUserId);
		// comment.setType(CommentEntity.TYPE_EVENT);
		// comment.setTime(ClockUtil.getCurrentTime());
		// comment.setTaskId(taskId);
		// if (userId!=null) {
		// comment.setAction(Event.ACTION_ADD_USER_LINK);
		// comment.setMessage(new String[]{userId, type});
		// } else {
		// comment.setAction(Event.ACTION_ADD_GROUP_LINK);
		// comment.setMessage(new String[]{groupId, type});
		// }
		// commentManager.insert(comment);
		// }

		return null;
	}

}
